<ul class="nav nav-list">
    <li <if condition="$nav eq 1">class="active"</if>>
    <a href="{:U('/Admin')}">首页</a>
    </li>
    <li <if condition="$nav eq 2">class="active"</if>>
    <a href="{:U('/Admin/Vote')}">投票</a>
    </li>
</ul>